Warp to Worlds 6,7, and 8:
--------------------------
Enter level 4-2 and proceed to the right until you come to the first set of
descending platforms. Just to the right, you will notice some blocks floating
in the air. Jump around below them and you'll reveal hidden blocks that you
can climb to reach the overhead blocks. Break them to produce a vine that you
can climb to a special bonus area. Head to the right from there to find a series
of warp pipes that will take you to worlds 6, 7, and 8.

Warp to World 5:
----------------
Keep to the ceiling and run past the exit pipe that would normally take you to
the end of Stage 4-2. To the right, you'll find a warp pipe that leads directly
to World 5.

Warp to Worlds 2,3, and 4:
--------------------------
As you ride the elevators near the end of the level, you can jump onto the ceiling and run along it to find a warp area that lets you skip directly to world 2, 3, or 4.

Unlockable Abilities and Modes:
-------------------------------
You can activate various perks and content by meeting the corresponding requirements, as indicated below.

All Weapons Pierce - Defeat 200 armored enemies, plus finish the game on any difficulty setting.